BBC Worldwide has sold an 85% stake in BBC Audiobooks, which publishes titles including Richard Burton's Under Milk Wood, Winnie the Pooh and The Hitchhiker's Guide to the Galaxy, in a deal understood to be worth at least £10m.

It is being acquired by AudioGo, a company set up by a former senior executive at Polygram, Michael Kuhn, and six partners. BBC Audiobooks, which publishes products on CD and downloadable digital formats, employs 140 staff, with the majority – 104 – in Bath and the rest in Rhode Island, New York.

The deal is likely to be the first of several disposals of assets considered non-core by BBC Worldwide, the corporation's commercial arm. The sale of a stake in BBC Magazines, which publishes titles including the Radio Times and Top Gear, is expected to form part of this process.

A spokesman for BBC Worldwide said that the deal "secures the future of the business and its predominantly Bath-based staff".

BBC Worldwide declined to reveal the value of the deal, although it is understood to be in the region of £10m to £15m.

Specific revenues figures for the audiobooks business are not available, although BBC Worldwide said that it was profitable in the 12 months to the end of March.

In the same period, the audio and music division, which includes BBC Audiobooks, had revenues slip from £27.2m to £25.9m and profits fall by 43% year on year.

"I'm pleased to announce the successful conclusion of the sale process we initiated last year," said John Smith, chief executive of BBC Worldwide. "Sale proceeds will be reinvested in our international businesses, supporting future returns to the BBC, and therefore benefiting the licence fee payer."

The company will trade as AudioGo but continue to publish BBC-sourced content under the BBC Audiobooks brand. About 20% of audio content produced by BBC Audiobooks is from the corporation's content.

BBC Worldwide said that it had struck the deal because it was able to provide the substantial investment the business requires to keep pace with the shift to digital consumption.

"The partners in AudioGo Ltd are committed to building on the past achievements of BBC Audiobooks as it enters the digital age," said Kuhn, chairman of AudioGo. "Opportunities are many and exciting and we will immediately get to it with Managing Director Mike Bowen and his team, and in partnership with BBC Worldwide, to create new offerings to our customers worldwide."

BBC Worldwide said that the audio and music business operated in "challenging markets" last year, adding that although digital downloads are growing and now account for almost 30% of units sold, the business is "strategically non-core and we believe a faster transition from physical to digital distribution can be achieved".

In 2006 BBC Worldwide struck a deal to sell an 85% stake in BBC Books, which has published books by David Attenborough, Simon Schama and Delia Smith, to Random House, which merged it into its Ebury Publishing division. The year before BBC Worldwide formed a partnership, along similar 85/15 lines, with Pearson Education to publish BBC-branded educational products and services.

Last year BBC Worldwide was forced to look at how to curtail its scope after critics argued that deals, such as its controversial acquisition of Lonely Planet in 2007, proved it was being too expansionist and harming commercial rivals.

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